Based on its quarterly sales forecast, Charming Shoes projected sale volumes for its shoes are first quarter: 12,000 units, second quarter: 15,000 units. The beginning inventory in the first quarter is 6,000 units. Ending inventory for each quarter should be 50% of the next quarters sales. How many pairs of shoes should Charming Shoes produce in the first quarter?

a. 13 500

b. 25,500

c. 12 000

d. 19 500